Cylinder check mechanism for duplicating machines



Dec. 30, 1952 R. M. FORD ETAL 2,623,459

CYLINDER CHECK MECHANISM FOR DUFLICATING MACHINES Filed April 27, 1950 2 SHEETS-SHEET 1 Dec. 30, 1952 R, FQRD ETAL 2,623,459

CYLINDER CHECK MECHANISM FOR DUPLICATING MACHINES Filed April 27, 1950 2 SHEETS-SHEET 2 W AGENTS Patented Dec. 30, 1952 CYLINDER CHECK MECHANISM FOR DUPLICATING MACHINES Ronald Max Ford and George Thomas Butler, Sparkbrook, Birmingham, England; said Butler assignor to Frank R. Ford Limited, Sparkbrook, Birmingham, England, a British company Application April 27, 1950, Serial No. 158,381 In Great Britain May 7, 1949 2 Claims.

- This invention relates to duplicating machines .of the kind in which a copy sheet and a master sheet bearing in reversed script the matter to be reproduced are passed in pressure contact between a cylinder which carries the master sheet and a pressure roller, the copy sheet being moistened before being bought into contact with the master sheet.

In machines of this kind it is usual to provide the cylinder with a shaft and to mount this shaft in bearings in opposite side members of a frame, and it is known to provide on the end of the cylinder and on the frame co-operating check members for checking the rotary movement of the cylinder at a certain position in each revolution thereof to ensure that when a copy sheet is fed in the leading end of the master sheet is in the correct position relative to the leading end of the copy sheet, so that the matter on the master sheet will be reproduced on the copy sheet in the desired position in relation to the end of the copy sheet.

Such means have usually consisted of a cam or disc on the end of the cylinder, said cam or disc having a notch in its periphery, and the other cheek member taking the form of a lever pivoted to the frame and pressed by a spring against the periphery of the cam or disc, the lever having a projection which engages the notch when the cylinder is in the check position. With this arrangement, as the lever is always in pressure contact with the periphery of the cam or disc, wear takes place on these parts and further wear takes place on the projection on the lever and in the notch in the periphery of the disc or cam.

The object of the present invention is to provide an improved construction.

According to one feature of the present invention one of the check members is formed as a spring-loaded lever which normally engages a stop, which lever is out of contact with the other cheek member during the major part of the rotation of the cylinder and is engaged thereby only at and near the check position of the cylinder.

According to another feature of the present invention one of the check members is formed as a roller mounted for rotation.

The lever may be pivoted to the end of the cylinder, and the roller may be mounted for rotation on a pin projecting inwardly from the frame, the arrangement being such that pivotal movement of the lever in an inward direction towards the axis is limited by a stop, but as the cylinder revolves the inner edge of the lever comes into contact with the roller near the check position, and at the check position a notchin the lever engages the roller so as to check the rotary motion of the cylinder without positively preventing it. Continued pressure to rotate the cylinder causes the lever to move away from the roller, after which thelever again makes an inward movement towards the axis ofthe cylinder, which is limited by a stop. The invention is illustrated in the accompany ing drawings wherein:

Figure l is a view in side elevation of a du plicating machine according to the present invention.

Figure 2 is a part section on the line 2-2 in Figure 1.

Figure 3 is a section on the line 3-3 in Figure 2.

Figure 4 is a section on the line i4 in Figure 2.

In the construction shown in the accompanying drawings the cylinder [6 is made of a length of tube having end plates II which are secured in the tube at a short distance from each end. A spindle l2 extends through the cylinder, or may be made in two parts one attached to each end plate at the centre, and the ends of this spindle, or these spindles, engage in bearings I3 which project inwardly from the side members M of the frame of the machine. The said bearings i3 are formed on or attached to a plate secured to the inner surface of the side member [4 of the frame, and this plate may be of circular or other form and carries a pin [5 projecting parallel to the said bearing, and on the pin is mounted a roller [6. This pin i5 and roller 15 are mounted a suitable distance away from the actual bearing.

Pivoted to one of the end plates ll of the cylinder i8 is a lever ll. This lever is pivoted at one end on an axis l8 parallel to the axis of the cylinder, and at the opposite end the lever I! engages a stop pin I9 fixed to the end plate of the cylinder. The lever I! is thus housed within the cavity formed by the projecting end of the tube forming the cylinder [0.

On its inner edge at a suitable position the lever I1 is provided with a V-shaped notch 20, and operating between the back edge of the lever and the tube forming the cylinder I0 is a compression spring 2!, so that the lever is springloaded towards the axis of the cylinder, but such inward movement is limited by the stop.

The cylinder 29 may be rotated by means of a handle 22 and moistening means as generally indicated at 23 are provided for moistening the copy sheet 24 which is fed from a feed table 25. Pressure roller 26 is provided, supported and mounted for adjustment by means. which are more specifically described in our copending application Serial No. 158,382 filed herewith.

When the cylinder I0 is in position in the machine and is rotated the lever is out of contact with. the roller for the major partof the revolution of the cylinder, but as the cylinder approaches the check position the roller engages the inner edge of the lever, and at the check posi-- tion the roller is engaged by the il -shaped notch in the lever. Thus, the rotary motion of the cylinder is checked, but the cylinder is not positively locked and rotation can be continued by exercising a reasonable amount of pressure on the usual handle provided for rotating the cylinden.

When; this is done the lever rides clear of the rollenmaking a pivotal movement away from the axis of the cylinder as it does so. When the lever has. moved away from the roller it moves back into" its normal position under the influence of spring.

What we claim then is:

I. Inaduplicating machine of the kind specifled, a frame, a cylinder for carrying a master sheet rotatably' mounted in said frame, said cylinder having'an end face and being extended beyondv the end face to provide a recess at the end of, the, cylinder, con-operating. check members on the cylinder and on the frame for checking the rotary movement of the cylinder during each revolution, said co-operating check members comprising a lever. having a notch in one side thereof pivotally mounted at its one end on the said end face on an axis parallel to the axis of; the cylinder, at stop on the end face of the der, anda check member mounted on the adjacent; part of the machine frame, projecting into said recess and co-operating with the notch in said lever, for checking rotation of the cylinder at a certain position in each revolution, said lever being out of contact with said check member during. the major part of a revolution and being engaged thereby at and near the check position.

2. In a duplicating machine of the kind specified, a frame, a cylinder for carrying a master sheet rotatably mounted in said frame, said cylinder having an end face and being extended beyond the end face to provide a recess at the end of the cylinder; co-operating check members on the cylinder and on; the frame for checking the rotary movement of; the cylinder during each revolution, said co -operating check members comprising a. lever pivotally mounted at its one end on the said end face on an axis parallel to the axis of. the cylinder, a stop on the end face of the cylinder normally engaged by the other end of said lever to prevent inward pivotal movement of the lever towards the axis of the cylinder, a springacting between saidlever and theinside of the cylinder'urging said leverso as to engage the stop, said lever, stop and spring being all housed With-in the said recess at the end of the cylinder, a pin projecting inwardly from the frame into said recess and a. roll-er mounted for rotation on said pin, cooperating with said lever, for checking rotation of the cylinder at a certainposition in each revolution, said lever being The following references are of record in. the file of this patent:

UNITED STATES PATENTS,

Number Name Date- 1,317,l86 Flanigan Sept. 30, 19:19

FOREIGN PATENTS Number Country Date 580,577 Great'Britain Sept. 12,1946 590,153

Great Britain July 9'. I947 

